Among many modern electronic device module designs is a device known as the ball grid array (BGA), which comprises an insulative substrate having one or more integrated circuit chips and other devices on an upper surface, and a matrix array of solder ball terminals on a lower surface. Because the solder ball terminals are located over the entire lower surface of the module, a greater circuit density can be accommodated than is true of conventional modules in which the terminations are all included around the periphery of the module. After BGA modules have been constructed, they of course must be tested, which requires a temporary connection to all or most of the solder balls contained on the lower surface.
Accordingly, there is a long-felt need in the industry for testing methods that would permit easy temporary connection to all of the terminals of a ball grid array, and which would permit the prompt and convenient testing of successive electronic devices having ball grid arrays.